Hi Keith,
Well ideally secondary SWF (whether external or not) containing any ABC code can't be reloaded on iOS and there is no "limit" of using any AS code to make reload work. But your case looks like an exception to me. Can you share your app(with sources) or may be part of your app which can explain your case at dropbox and share link with me @nimisha1@adobe.com?
Thanks,
Nimisha